Ulster winger Tommy Bowe will undergo surgery on his knee later this week and looks a doubt for Ireland's Six Nations campaign.

Bowe was stretchered off in the 77th minute of Ulster's match with the Northampton Saints on Saturday evening and there were immediate fears that the 28-year-old had suffered a severe injury. And Ulster have confirmed those fears saying that the winger has "sustained significant lateral ligament damage to his right knee".

Ulster are reluctant to reveal how long Bowe will be out of action for with a statement saying: "At this stage it is not possible to put a timescale on how long his recovery period will be. A further update on this will be issued following the surgery, when the full extent of the injury will be known."

Mark Anscombe, Ulster's coach, said post-match that the winger's injury looked "serious" and it seems likely that he will have to plan for their final two Pool matches of the Heineken Cup in January without the British & Irish Lions Test winger.

Ireland kick-off their Six Nations campaign against Wales on February 2 and Bowe looked set to play a key role in their charge for the northern hemisphere title. But Ireland boss Declan Kidney will now face an anxious wait to see how long the winger is out of action for with Bowe a doubt for that campaign.

Ulster are also monitoring the fitness of Dan Tuohy and Paddy Jackson. Tuohy injured his calf during the match while Jackson sustained a dead leg - Ulster will give an update on the duo's condition on Monday.